A packaging bag with a reclosable tape typically used as a packaging material for packaging various articles such as foods and medical products is provided with a reclosable tape (engaging member) having a belt-like shape at an opening of the bag, the reclosable tape including a pair of a male member and a female member that are engaged with each other in a manner openable and reclosable.
As a typical method for manufacturing such packaging bag with the reclosable tape that allows opening and resealing of the opening of the bag, there is typically and widely used a method including making the reclosable tape in advance and heat-sealing the reclosable tape to a base material film as a component material of a bag body.
In an arrangement of such reclosable tape, the reclosable tape has been formed from a resin that is the same as that forms an innermost layer (sealant layer) of the base material film so that the reclosable tape can be heat-sealed to the base material film with ease. The innermost layer of the base material film has been typically formed from a low-density polyethylene (LDPE) or a propylene (PP), and in such case, the low-density polypropylene (LDPE) or the polypropylene (PP) has also been used as a component material of the reclosable tape, the reclosable tape heat-sealed to the sealant layer (the innermost layer) of the base material film.
Meanwhile, there has also been proposed another arrangement of a reclosable tape in which an engaging portion including a male member and a female member and a seal portion that is welded to a sealant layer (innermost layer) of a bag body are formed from different resins (see, for instance, Patent Document 1). In the reclosable tape with such arrangement, the male member and the female member are formed from a resin having a melting point higher than a resin that forms the seal portion, so that the male member and the female member can be prevented from being deformed when the reclosable tape is heat-sealed to the bag body.
[Patent Document 1] JP-A-10-297652 (claim 1 and FIGS. 1 and 4)